In an unfortunate development for the anti-smoking pharmaceutical market, the FDA will now require manufacturers to add severe side-effect warnings to the packaging of two of the industry's most popular drugs.

Smoking-cessation meds Chantix and Zyban (better known as anti-depressant Wellbutrin) will bear suicide warnings after researchers discovered abnormally high rates of depression and self-harm among study subjects. The FDA's most serious black box mark will also appear on every Chantix box. To temper backlash, the FDA's Evaluation and Research director restated their general support for the drugs, calling them "effective aids" in the battle to quit smoking. But the announcement will undoubtedly fuel public concern and lead to lower prescription rates for a drug already suffering from a short history of bad press.

In a standard check-up procedure, the FDA reviewed data from clinical studies involving these drugs and found an abnormally high instance of adverse events. Official reasons given for the new requirement: reports of depressive behavior, personal hostility and suicidal ideation among subjects taking the drugs to curb their smoking habits. Chantix studies in particular revealed a disturbing number of suicides.

The precise neurological underpinnings of these problems remain unknown. Some name nicotine withdrawal - longtime smokers who quit abruptly often feel increasingly anxious, restless and depressed, much like the to the subjects in the survey. But the numbers remain troubling. 188 Chantix subjects attempted and 98 completed suicide since 2006, and these rates were far higher than those in matching control groups. The Zyban total was significantly lower at 14, this difference eliminating the need for a second black box.

A good majority of America's 50 million smokers claim they want to quit. But its not as easy as we'd like it to be. Our own president has demonstrated the difficulties of smoking cessation through his widely reported struggle to end a long-held cigarette habit. The FDA's announcement will damage the products' reputations, but the fact that they've clearly worked for thousands in the past should ensure that many struggling smokers will continue to find effective treatment with Chantix and Zyban.